Purging of porogen from UV cure chamber

Abstract

An apparatus for purging a space in a processing chamber comprises a source of a purge gas; an inlet portion of a purge ring; an inlet baffle located in the inlet portion and fluidically connected to the source of purge gas; and an exhaust portion of the purge ring. The inlet portion and the exhaust portion define a ring hole space having a 360° periphery. The inlet baffle preferably surrounds not less than 180° of said periphery. The inlet baffle is operable to convey purge gas into the ring hole space. The exhaust portion is operable to convey purge gas and other matter out of the ring hole space. Cleaning of the purge ring and other structures in a processing chamber is conducted by flowing a cleaning gas through the inlet baffle. Methods and systems using a purge ring are particularly useful for purging and cleaning porogens from a UV curing chamber. Some embodiments include a gas inlet plenum and an exhaust channel but not a purge ring.

Description

RELATED APPLICATIONS[0001]This application is a divisional application, claiming priority under 35 USC §§120 and 121 and 37 CFR 1.53(b) of co-owned U.S. patent application Ser. No. 11 / 391,134, filed Mar. 28, 2006, by Smargiassi et al., now abandoned, which claims the benefit under 35 USC 119(e) of U.S. Provisional Application Ser. No. 60 / 742,844, filed Dec. 5, 2005. This application is also a continuation-in-part application, claiming priority under 35 USC 120, of co-owned U.S. patent application Ser. No. 11 / 115,576 filed Apr. 26, 2005, now U.S. Pat. No. 8,137,465 having the title “Single Chamber Sequential Curing of Semiconductor Wafers”. These parent applications are incorporated herein by reference for all purposes.FIELD OF THE INVENTION[0002]The invention is related to the field of integrated circuit fabrication, in particular to methods and apparatuses for purging and cleaning process chambers used in the annealing and curing of semiconductor wafers.BACKGROUND OF THE INVENTION[...

AI Technical Summary

Benefits of technology

[0008]The invention helps to solve some of the problems mentioned. Embodiments in accordance with the invention are particularly suitable for purging and cleaning curing chambers used to anneal and to cure interconnect-level dense or porous low-k dielectrics. As a result, it is possible to cure a large number of wafers, for example, 25 or more wafers, before cleaning the quartz window and the curing chamber.

[0010]Typically, in curing operations in accordance with the invention, a combination of UV light and heat facilitates curing of low-k films at relatively low temperatures. For example, wafers with a previously deposited PECVD (plasma enhanced chemical vapor deposition) film are introduced into a curing chamber in accordance with the invention, where they are exposed to a uniform UV lamp source to modify the film properties. At the same time, the wafer is heated to a uniform temperature, typically 450° C. or less. With porous low-k films, UV radiation facilitates removal of porogens and mechanically strengthens the dielectric film for further processing.

[0012]Generally, embodiments in accordance with the invention provide purging of cure chambers that significantly reduces cleaning requirements during wafer processing compared to the prior art. In some embodiments in accordance with the invention, more than 100 porogen containing wafers are processed before a chamber clean is required, resulting in a throughput that is as much as 20 times higher than the industry average.

Problems solved by technology

These doping methods, however, generally cannot produce materials with dielectric constants lower than about 2.6.

These thermal processes, however, have certain difficulties.

As is well known in the field, these conditions can damage copper containing devices.

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